WordReference Random House Learner's Dictionary of American English © 2026
im•prop•er /ɪmˈprɑpɚ/USA pronunciation
adj.
WordReference Random House Unabridged Dictionary of American English © 2026- not belonging or applicable:drew some improper conclusions.
- not agreeing with what is proper:improper conduct.[ it + be + ~ (+ for + obj) + to + verb]:It was improper (for you) to make that offer.
- abnormal;
irregular:signs of improper functioning. - not correct:improper laboratory procedures.
im•prop•er
(im prop′ər),USA pronunciation adj.
im•prop′er•ly, adv.
im•prop′er•ness, n.
- not proper;
not strictly belonging, applicable, correct, etc.;
erroneous:He drew improper conclusions from the scant evidence. - not in accordance with propriety of behavior, manners, etc.:improper conduct at a funeral.
- unsuitable or inappropriate, as for the purpose or occasion:improper attire for a formal dance.
- abnormal or irregular:improper functioning of the speech mechanism.
- Latin improprius. See im-2, proper
- 1535–45
im•prop′er•ness, n.
- 1.See corresponding entry in Unabridged –3. inapplicable, unsuited, unfit.
- 2.See corresponding entry in Unabridged indecorous. Improper, indecent, unbecoming, unseemly are applied to that which is unfitting or not in accordance with propriety. Improper has a wide range, being applied to whatever is not suitable or fitting, and often specifically to what does not conform to the standards of conventional morality:improper diet; improper behavior in church; improper language.Indecent, a strong word, is applied to what is offensively contrary to standards of propriety and esp. of modesty:indecent behavior, literature.Unbecoming is applied to what is esp. unfitting in the person concerned:conduct unbecoming a minister.Unseemly is applied to whatever is unfitting or improper under the circumstances:unseemly mirth.
- 1, 3.See corresponding entry in Unabridged fitting, suitable.
- 2.See corresponding entry in Unabridged proper.